KR20180127387A - Apparatus and method for testing tires - Google Patents

Abstract

A device (1) for inspecting a tire, comprising: a support frame (2); A flange (3); And an acquisition system (4) for acquiring a three-dimensional image of the surface of the tire; , Wherein the acquisition system is installed in a support frame, the acquisition system comprising: a matrix camera (5); A linear laser source 7; And a first section (14) and a second section (31) formed between the first section (14) and the second section (31) of the optical axis (6) which are symmetrical to each other with respect to the normal of the reflective surface at the incident point of the reflective surface The angle 50 is an obtuse angle and a second angle 51 formed between the first section 16 and the second section 32 of the propagation axis 9 with respect to the normal of the reflective surface at the incident point of the reflective surface ) Is a device that inspects obtuse tires.

Description

Apparatus and method for testing tires

The present invention relates to an apparatus and a method for inspecting a tire in a tire production line. In particular, the present invention relates to an apparatus and method for inspecting a tire in a tire production line by acquisition of an image of the inner surface of the tire and further processing of the image, for example, to detect the presence of detectable defects on the surface of the tire .

"Check" means a tire quality inspection.

The term "tire" typically refers to a completed tire, i.e., a tire after the manufacturing, molding or reinforcement step, but possibly a green tire after the molding step and / or the vulcanization step.

Typically, the tire has an axial midline plane that is substantially orthogonal to the axis of rotation and has a substantially toroidal configuration about the same axis of rotation during operation, and the plane is typically formed of a material having a generally tortuous structure, such as a tread pattern and / Is a geometrically (substantially) symmetrical plane (except for any small asymmetry).

A tire has at least one (preferably at least one) < RTI ID = 0.0 > tapered < / RTI > tapered end flap having opposing end flaps coupled with respective annular anchor structures substantially perpendicular to the axis of rotation identified as "bead " And a carcass structure including a carcass ply. In a "tubeless" tire, the radially inner carcass ply is preferably made of an elastomeric material commonly referred to as a "liner ", which has optimal airtight properties and extends from one bead to another bead Lt; RTI ID = 0.0 > butyl-based < / RTI > One or more belt layers having a fabric or metal reinforcing cords may be joined radially outwardly to the carcass structure. The tread band is applied radially outwardly to the belt layer. The individual side inserts of the elastomeric material are further applied to the axially external position on the side of the carcass ply, each extending from the annular end edge of the tread band to the bead in each annular anchor structure.

"Crown" refers to a tire portion that includes a tread band, a belt layer, and a corresponding carcass structure portion radially inward of the tire.

The "sidewall" means one of two tire portions that extend substantially radially from both sides of the crown to the bead and are reciprocally facing.

"Shoulder" refers to the portion of the tire that joins the crown and the side wall (i.e., the two shoulders are located in the radially and axially outer circular "edges" of the two tires). Each shoulder has a circular deployment portion that is substantially perpendicular to the axis of rotation.

The outer or inner surface of the tire represents a surface that is visible after joining the tire to the mounting rim of the tire, and a surface that is no longer visible after joining.

The term "inner tire space" refers to the set of points intersecting a tire in two sections disposed opposite to a point at which a straight line passing through a point considered relative to the axis of the tire is considered.

The term "cycle time" in a production line that includes at least one work station, preferably a plurality of work stations, and which is inserted into a production plant of a tire means that at the maximum speed, It means the maximum time it takes to pass through one workstation to be manufactured. For example, the addition time may be about 20 seconds to 120 seconds.

The terms "lower "," high ", "lower "," upper ", such as relative positions of elements such as tire components, tires, devices, devices, etc., relative to the ground during use, Lt; / RTI >

It is to be understood that "substantially perpendicular" to geometric elements (e.g., straight lines, planes, surfaces, etc.) forms an angle of 90 +/- 15 degrees, preferably 90 +/- 10 degrees with these elements it means.

Substantially "with the geometric elements means that it forms an angle of 0 +/- 15, preferably 0 +/- 10 with the elements.

"Angle formed by straight lines and planes" means an acute angle formed by a straight line and a perpendicular projection to a plane.

"Angle formed by straight line and surface" means an acute angle formed by perpendicular projection to a plane perpendicular to the surface at a point intersecting a straight line and a straight line.

"Angle formed by two straight lines" means an acute angle formed by two straight lines if they are incident on one point. When two straight lines form an angle, it means an acute angle formed by two straight lines passing through the same point and parallel to two straight lines.

&Quot; Optical ", "optical ", and the like, are intended to have at least a portion of the spectrum that is within the extended range of the optical band and that does not necessarily lie strictly within the optical band (i.e., 400 to 700 nm) Refers to electromagnetic radiation used to reach from ultraviolet to infrared (e.g., wavelengths comprised between about 100 nm and about 1 m).

The term "digital image" or similar term "image" generally refers to a data set typically contained in a computer file, and includes (typically two-dimensional and matrix type, × M rows) The finite set of (usually two-dimensional) angular coordinates correspond to a set of numerical values (which may represent different types of sizes). For example, a monochromatic image such as a set of values (e.g., an image of a "grayscale") matches a single value of a finite scale (typically 256 levels or tones) The set of values in a color image represents the intensity level of multiple colors or channels, typically the primary color (e.g., RGB color models red, green, and blue, whereas in the CMYK color model, cyan, Magenta, yellow and black). The term "image" does not necessarily imply an actual display of the image.

All references to a particular "digital image" (e.g., a two-dimensional digital image initially obtained on a tire) may include one or more digital processing operations (e.g., filtering, equalization, Quot; openness ", tilt calculation, "smoothing ", etc.).

The term " 2D image "or the" 2D "of the surface refers to the digital image of each pixel associated with information representing the reflectivity / diffusivity and / or color of the surface, such as an image detected from a common camera or a digital camera .

The term " 3D image "or" 3D "of the surface refers to a digital image of each pixel associated with surface elevation information.

Refers to an optoelectronic device that includes an image sensor (or sensor) and is designed to acquire a two-dimensional digital image, which includes an image plane and an image plane (although the present invention is not limited to this purpose, Lt; / RTI > of the objective lens).

"Sensor" means a set of light-sensitive elements (so-called "pixels") capable of converting incident light into an electronic signal, e.g., by CCD or CMOS technology. The term pixel is used to denote both a single light-sensitive element of the sensor and a single element that forms the digital image defined above, and each pixel of the sensor typically corresponds to a pixel of the image.

A "matrix camera" has pixels arranged in a two-dimensional comparable length according to a rectangular matrix (e.g., the two dimensions are less than the first order, such as the 4x3 or 3x2 form). Typically, the diagonal length of the sensor matrix is several tens of millimeters. By extension, the "matrix" image is a two-dimensional digital image acquired by a matrix camera.

The "optical axis" of the objective lens represents the line in which the rotational symmetry of the objective lens exists.

Means a plane of an object point that is focused by an objective lens on a sensor, that is, a ray originating from an object point on the focal plane is projected onto a sensor plane (image plane) at each individual point .

"Depth of field" is defined as the distance from the plane of the plane that lies next to the focal plane of each point, which, when projected by the objective lens on the sensor plane, forms an image engraved on a circle of predeterminedconstitution (e.g. having a diameter of 5-10 microns) ≪ / RTI >

"Linear laser source" means a laser source designed to emit a linear laser beam that passes through a laser source and belongs to a propagation plane, such as the propagation direction, and the laser beam lies in the " propagation plane " The intersection of a linear laser beam with a physical surface having reflective / diffusive properties, such as the surface of a tire, creates a "laser line ".

A "reflected laser line" is an image of a laser line on a surface in an image acquired by a camera.

A "surface linear portion" means a surface portion having a dimension dimension greater than another dimension orthogonal thereto, and is typically at least two orders of magnitude larger. The small dimension of the linear surface portion is typically 0.1 mm or less.

The "reflective surface" of a counter-clock element is defined by the actual reflection surface and the reflection using at least one inner reflection (by total reflection or mirroring of at least one inner surface) or a refraction prism that converts light by refraction, As in the case of a prism. In practice, a prism can be modeled as a reflective surface with a reflective action, such as a prism (for a given laser wavelength).

In the context of the manufacture and processing of wheel tires, the applicant has performed quality checks on the finished product to prevent the introduction of tires or defective tires that do not meet design specifications and gradually adjust the devices and machines used I felt the need to improve and optimize the execution of the tasks performed in the production process.

This quality inspection includes, for example, steps performed by an operator who devotes a fixed amount of time for the visual and tactile inspection of the tire; In view of the operator's own lightness and sensitivity, if the operator suspects that the tire does not meet a certain quality criterion, the tire may be inspected and / or suitably inspected by a more detailed operator to specifically identify any structure and / Additional testing is done through the equipment.

WO 2015/122295 A1 discloses an apparatus for obtaining a three-dimensional image of the inner surface of a tire comprising a light source, a mirror and a camera, the mirror being constructed in such a way that it rotates about a rotation axis line. do.

WO 2015/044196 A1 discloses a three-dimensional image acquisition device for the inner surface of a tire, comprising a laser illumination means, an image acquisition means and a reflector optically interposed between the illumination means and the illuminated area of the tire surface. The laser illumination means may project an illumination line on the surface of the tire and the acquisition means comprises a matrix camera oriented according to a triangulation angle formed between the optical axis of the camera and the optical axis of the laser.

In the field of tire quality testing, the applicant has developed a technique for inspecting the inner surface of a tire by optical acquisition of the digital image of the inner surface of the tire and subsequent processing of the digital image, for example to detect the presence of defects in the vicinity of the surface or surface I set the problem. Defects to be detected may be, for example, irregularities on the surface of the tire (unvarified compounds, deformations of shape, etc.), structural irregularities, cuts,

In particular, applicants have recognized that obtaining and analyzing three-dimensional images of the inner surface of a tire is advantageous.

For example, 3D technology can be used to provide 3D deformations, defects, or protrusions of material on the inner surface of a tire, typically defects or bubbles, or elevated wadding or knurling, especially at high image quality, such as resolution below 10 microns. It can be used to detect some features.

Applicants have discovered that an inspection instrument can be used "within a line" in a tire production plant and that the inspection itself must be performed within a reduced time, less than the cycle time, which reduces cost and / or overall dimensions .

Applicants have found that in a tire quality inspection method that optically acquires a three-dimensional image of an inaccessible inner surface portion such as an inner surface, an inner sidewall or an inner bead or an inner shoulder by laser triangulation techniques, It has been found that it is difficult to obtain a matrix image of a surface portion illuminated by lines. This is due to the variety of tires to be inspected which have very different dimensional characteristics (outer inner diameter, fitting, cord, bead length, different shape and width of sidewalls, dimensional parameters such as dimensional differences).

The Applicant has also found that, in the face of these difficulties, the apparatus for acquiring three-dimensional images disclosed in WO 2015/12295 A1 and WO 2015/044196 A1 is complicated in structure and / or operation, and / or is too heavy. All of this makes it difficult to insert the device into an industrial production line, which can lead to interference risks (due to weight and dimensions), cost (e.g., high maintenance costs), and / Many downtime events) tend to increase.

Applicants have recognized that a solution to the above-mentioned problems can be achieved with design changes of the acquisition system in terms of placement of the reflective elements.

More specifically, the Applicant has found that, before and after reflection on the reflective surface, a first obtuse angle between the optical axes of the camera, and a reflective surface of the reflective element to form a second obtuse angle between the propagation axes of the linear laser beam before and after reflection on the reflective surface It is possible to obtain a compact 3D image acquisition device which is designed to be inserted into a tire to obtain an image of three different areas (inner shoulder, inner sidewall, and inner bead) and which is movable and spatially handled.

According to a first aspect of the present invention, there is provided an apparatus for inspecting a tire of the present invention.

Preferably, a support frame is provided.

Preferably, a flange attached to the support frame is provided for attaching the support frame to the moving member of the device.

Preferably, an acquisition system for acquiring a three-dimensional image of the surface of the tire is provided, wherein the acquisition system is installed in a support frame.

Preferably, the acquisition system includes a matrix camera having an optical axis.

Preferably, the acquisition system includes a linear laser source designed to emit a linear laser beam having a propagation plane and a propagation axis.

Preferably, the acquisition system includes a reflective element having a reflective surface that intersects both the propagation axis and the optical axis to identify a first section and a second section of the propagation axis and a first section and a second section of the optical axis, respectively.

Preferably, the first section and the second section of the propagation axis are linear sections incident on the reflective surface at respective incidence points, wherein the first section and the second section of the propagation axis are arranged at a line perpendicular to the reflective surface at the individual incidence point Mirrors are symmetrical to each other.

Preferably, the first section and the second section of the optical axis are linear sections incident on the reflective surface at the individual incidence points, wherein the first section and the second section of the optical axis are perpendicular to a line Are mirror symmetrical with respect to each other.

Preferably, each of the first sections is positioned at a side of the linear laser source and the matrix camera with respect to the point of incidence, respectively.

Preferably, the first angle formed between the first section and the second section of the optical axis is an obtuse angle.

Preferably, the second angle formed between the first section and the second section of the propagation axis is an obtuse angle.

According to a second aspect of the present invention, the present invention relates to a method of inspecting a tire.

Preferably, arranging the tires to be inspected is contemplated.

Preferably, the step of arranging the apparatus for inspecting the tire according to the first aspect of the present invention is considered.

Preferably, the step of inserting at least the reflective element into the tire interior space is considered.

Preferably, a step of illuminating the linear portion of the inner surface of the tire with a linear laser beam is used to create the laser line.

Preferably, a step of acquiring a matrix image of a surface portion comprising a linear portion of the inner surface is contemplated.

Preferably, the matrix image comprises a reflected laser line representing a linear line.

Preferably, in the matrix image, the step of identifying the reflected laser line is considered.

Preferably, the step of processing the reflected laser line through triangulation is considered to obtain a three-dimensional image of the linear surface portion containing information about the elevation profile of the linear surface portion.

According to a third aspect of the present invention, there is provided a station for inspecting a tire in a tire production line.

Preferably, a support is provided and the support is designed to rotate the tire about the axis of rotation of the tire and to support the tires set on the side walls.

Preferably, there is provided a device for inspecting a tire according to the first aspect of the present invention.

Preferably, the device is mounted on a moving member of the device.

The Applicant has found that by eliminating the need to place the reflective element very close to the inner surface of the tire, such as the inner surface of the crown, which creates a risk of collision between the inner surface and the reflective element, since the first angle and the second angle are obtuse, (Optical axis in the first section) with respect to the axial center line plane, which also results in the risk of collision between the beads and the parts of the device (such as the frame) or the tilting due to contact between the beads and the device, It is believed that it is possible to illuminate inaccessible parts of the inner surface of the frame, such as the inner shoulder, without tilting.

This technical feature enables optimum dimensioning and placement of the elements of the device, which is structurally simple, compact, easy to handle, and designed to be used to acquire images of the inner surface of both the bead and sidewall and shawl .

The present invention may further comprise one or more of the preferred features disclosed below in one or more of the above aspects of the invention.

Preferably, the third angle formed between the optical axis and the reflective surface in the first section or second section is no more than 40 degrees.

Preferably, the third angle formed between the optical axis and the reflective surface in the first section or second section is 20 DEG or greater.

Preferably, the fourth angle formed between the propagation axis and the reflective surface in the first or second section is at least 40 degrees.

Preferably, the fourth angle formed between the propagation axis and the reflective surface in the first section or second section is 20 DEG or greater.

Preferably, the third angle is at least 30 degrees.

Preferably, the fourth angle is at least 30 degrees.

The selection of such angular values enables optimization of the dimensions, construction, and versatility of the device, in addition to ensuring the obtuse angle of the first angle and / or the second angle.

Preferably, the matrix camera, the linear laser source, and the reflective element are integrally secured to the support frame at respective fixed positions relative to the support frame. Preferably, the support frame is a substantially rigid body. In this way, the device is simple in structure and operation and reliable because there are no moving parts for the frame.

Preferably, the support frame includes an elongated upright portion having a major deployment along a first direction, the upright having a first end on which the flange is mounted and a second end on the opposite side of the first end along the first direction, Respectively.

Preferably, the support frame includes an elongated crossbar having a major deployment along a second direction, the crossbar extending along a first end and a second direction at a second end of the upright, The second end is a free end, and the reflective element is installed at the second end of the crosspiece. The crosspiece is rigidly attached to the upright portion at the second end, for example, and integrally formed with the upright portion.

Preferably, the first direction and the second direction are substantially perpendicular to each other, more preferably perpendicular.

Preferably, the first section of the optical axis and / or the first sector line of the propagation axis is substantially parallel to the second direction.

Preferably, at least the propagation plane in the first section of the propagation axis is substantially parallel to the first direction.

The elongated shape of the upright and crosspiece, and the spatial relationship between and relative to the optical axis and / or propagation axis and / or propagation flatness, as well as acquiring images of both the inner surface of the sidewall and the inner surface of the shoulder Facilitates changes in the instrument to obtain an image of the inner surface of the bead after proper movement (translation and / or tilting) of the instrument through the mobile system, preferably the robot arm.

Preferably, the first section of the optical axis extends from the matrix camera to the reflective surface.

Preferably, the first section of the propagation axis extends from the matrix camera to the reflective surface.

That is, there are no additional elements that reflect the optical path between the laser and the matrix camera and the reflective element. In this way, the device is structurally simple and reliable.

Preferably, the linear laser source and / or the matrix camera is mounted on the support frame at the second end of the upright portion. This prevents the use of additional reflective elements having the advantages described above.

Preferably, the linear racer source and the matrix camera lie side by side. This contributes to the overall miniaturization of the device.

Advantageously, the first section of the optical axis and the first section of the propagation axis are in a common plane. Preferably, the common plane is substantially perpendicular to the propagation plane. In this way, system performance in terms of optics is optimized, besides making the structure of the device particularly reasonable.

Preferably, the fifth angle formed between the second section of the optical axis and the second section of the propagation axis is at least 5 degrees.

Preferably, the fifth angle is at least 10 degrees. This produces sufficient dynamic excitation of the reflected laser line to detect a high degree of change with sufficient sensitivity.

Preferably, the fifth angle is 40 DEG or less.

More preferably, the fifth angle is 35 DEG or less. In this manner, the dynamic excitation of the reflected laser lines is not too wide to prevent processing too heavy matrix images.

Preferably, the fifth angle is 25 DEG or less, more preferably 20 DEG or less. In this way, a three-dimensional image of the area of the large surface is obtained (and thus is easily spatially spatted in a narrow space) at a relatively reduced time while maintaining the overall small size and compactness of the device. In practice, the matrix image acquired and processed by the matrix camera is included (with respect to the pixel) in a dimension perpendicular to the reflected laser line for a given maximum excitation of the height to be detected, and thus is faster to process. As a numerical example, when the fifth angle is 15 [deg.], The solution only processes a matrix image of 2048x60 pixels to detect a maximum excursion of a surface height of about 25mm at a resolution of 1 pixel per 0.1mm .

Preferably, there are no additional reflective elements along the optical axis and / or propagation axis in addition to the reflective element, below the reflective element with respect to the propagation direction of the linear laser beam. In this way, the device is compact and reliable.

In one embodiment, the reflective element is a prism.

Preferably, the counter element comprises a base body, preferably in the form of a plate, and an optical element fixed to the base body with a reflective surface.

Preferably, the base body is integrally secured to the second end of the crosspiece.

Preferably, the reflective surface is a physical surface.

Preferably, the reflective surface is only one.

Preferably, the reflective surface is flat.

In this way, the device is simple to align the structure and / or installation, e.g. optical parts.

Preferably, the reflective surface 12 is the outer surface of the optical element 41 facing the linear laser source 7 and the matrix camera 5.

This solution, in which the reflective surface is on the proximal surface of the optically activated element, has a greater vulnerability because the reflective surface may be exposed to the risk of being damaged by accidental contact, but on the one hand, And all unnecessary deviations of the optical path of the laser. In addition, the invention described above makes it possible to keep the reflective element farther from the inner surface, thereby reducing the risk of the accidental contact mentioned above.

Preferably, the optical element and / or reflective surface and / or the base body are tapered from the proximal end to the distal end with respect to the matrix camera and / or the linear laser source. In this way, advantageously, the taper created by the inclination remaining between the optical axis and the propagation axis reduces the footprint of the reflective element at the end located closer to the inner surface during use. In particular, the taper coincides with the concave portion of the inner surface of the tire in the circumferential direction at the time of use. As a result, it brings the reflective element close to the inner surface and reduces the possibility of collision with the inner surface. For comparison, the rectangular plane of the reflective element creates a risk of collision between the inner surface and the distal edges of the tire, and creates a larger curvature of the inner surface on the centerline plane (i.e., the curvature radius on the midline plane Lt; / RTI >

Preferably, the matrix camera comprises a sensor defining an image plane, an objective lens having an optical axis, and a depth of field.

Preferably, the image plane forms an acute angle with a reference plane passing through the objective lens and perpendicular to the optical axis and a vertex on one side on which the linear laser source is arranged, Or less, more preferably an angle of 30 DEG or less, and more preferably an angle of 10 DEG or less. In this way, advantageously, preferably, the focal plane is inclined towards the propagation plane of the linear laser beam and the depth of field is formed around the propagation plane, which is the depth of field, the depth of field, so that the focus of the laser line fits better , The iris becomes the same. Reducing the aperture increases the depth of field, but it should be noted that this will lead to an increase in the laser illumination power, which has drawbacks of complexity / cost and / or laser safety.

Preferably, the acute angle between the image plane and the reference plane is 20 DEG or less.

Preferably, the acute angle between the image plane and the reference plane is 15 degrees or less.

Preferably, the acute angle between the image plane and the reference plane is at least 5 degrees. In this way, advantageously, the instrument is very compact and leads to a reduced lateral dimension because the body of the matrix camera (which extends along the normal to the image plane) is nearly tilted with respect to the laser source and the plane of propagation.

Preferably, the matrix camera is designed to obtain a matrix image of a portion of the surface, and in a separate machine body, the processing unit comprises, in a matrix image, at least one of a laser beam and a light of a linear portion of the surface portion Lt; RTI ID = 0.0 > a < / RTI >

Preferably, the processing unit is configured to process the reflected laser line through triangulation to obtain a three-dimensional image comprising information about the elevation profile of the linear portion of the surface portion.

Preferably, the matrix camera comprises a rectangular sensor having a larger dimension substantially parallel to the propagation plane, the larger dimension being smaller than the dimension orthogonal thereto by at least one dimension order. In this way, the sensor is structurally optimized to detect the matrix image with dimensions that fit the surface portion that needs to acquire the matrix image for laser triangulation.

Preferably, the step of selecting the sub-portion of the acquired matrix image along a direction substantially perpendicular to the reflected laser line in the matrix image is contemplated. Here, operations to identify reflected laser lines and process the reflected laser lines through triangulation are performed on the sub-part of the image.

Preferably, the processing unit is configured to select a sub-portion of the acquired matrix image along a direction substantially perpendicular to the reflected laser line in the matrix image, wherein the reflected laser line is identified, The tasks to process the lines are performed on the sub-part of the image. In this way, a smaller image can be processed without a sensor of a certain size.

Preferably, after the sub-portion selection operation of the acquired image, the number of pixels along a direction perpendicular to the reflected laser line is less than 200 pixels.

Preferably, the number of pixels is 100 pixels or less. In this way, advantageously, the 3D image is obtained at a high speed.

Preferably, the surface portion is located within the depth of field.

Advantageously, said surface portion lies in one plane substantially perpendicular to said propagation plane (and the optical axis is tilted with respect to the normal of said one plane). In such a situation, advantageously, the depth of field for focusing the maximum possible height excitation of the surface portion is smaller than the configuration in which the surface portion is substantially perpendicular to the optical axis.

Preferably, the step of translating the first inner surface area of the tire relative to the device such that a series of segmented linear portions of the first inner surface area are continuously located within the depth of field of the matrix camera at least in the propagation plane, In order to obtain a series of three-dimensional images of a series of delimited linear portions of the first internal surface area, the acquisition system includes steps of illuminating with a linear laser beam, acquiring an individual matrix image, Dimensional image obtained on a series of linear inner surface portions and successively activated during the translational movement to sequentially repeat the steps of processing the individually reflected laser lines and acquiring individual three- A complete three-dimensional image of the first inner surface portion is obtained in combination.

Preferably, the step of translating the second inner surface area of the tire relative to the device such that a series of segmented linear portions of the second inner surface area are continuously located within the depth of field of the matrix camera at least in the propagation plane, In order to obtain a series of three-dimensional images of a series of distinct linear portions of the second inner surface area, the acquisition system may include illuminating with a linear laser beam, acquiring an individual matrix image, Dimensional image obtained on a series of linear inner surface portions and successively activated during the translational movement to sequentially repeat the steps of processing the individually reflected laser lines and acquiring individual three- A complete three-dimensional image of the second inner surface portion is obtained in combination.

Preferably, the step of translating the third inner surface area of the tire relative to the instrument such that a series of segmented linear portions of the third inner surface area are continuously located within the depth of field of the matrix camera at least in the propagation plane, In order to obtain a series of three-dimensional images of a series of delimited linear portions of the third internal surface area, the acquisition system may include illuminating with a linear laser beam, acquiring an individual matrix image, Dimensional image obtained on a series of linear inner surface portions and successively activated during the translational movement to sequentially repeat the steps of processing the individually reflected laser lines and acquiring individual three- A complete three-dimensional image of the second inner surface portion is obtained in combination.

Preferably, the first inner surface area is the inner surface area of the shoulder of the tire.

Preferably, the second inner surface area is an inner surface area of the side wall of the tire.

Preferably, the third inner surface area is the inner surface area of the bead of the tire.

Preferably, the first and / or second and / or third inner surface area is a circumferential inner surface area.

Preferably, the tire to be inspected is arranged to lie horizontally on the side of the tire.

Preferably, at least an operation of inserting the reflective element into the inner space of the tire is performed from above.

Preferably, the first and / or second and / or third inner surface areas belong to the upper half portion of the tire with respect to the centerline plane.

Preferably, the circumferential inner surface area has a width along the axis of the tire of about 5 mm to 20 mm.

Preferably, the step of rotating the tire relative to the axis of rotation of the tire in order to translate the first and / or second and / or third inner surface area of the tire relative to the device is considered.

Preferably, the moving member of the device is a robot arm.

Preferably, the moving member of the device is an anthropomorphic robot arm.

Preferably, the moving member of the device is an anthropomorphic robot arm having at least five axes.

Are included herein.

Additional features and advantages will become more apparent from the detailed description of some exemplary and non-limiting embodiments of apparatus, methods, and stations for testing tires in a tire manufacturing line in accordance with the present invention. This description will be described below with reference to the accompanying drawings, which are provided for purposes of illustration only and are thus provided for non-limiting purposes.
1 is a partial perspective view of an apparatus for inspecting a tire according to the present invention.
Figure 2 is a side view of the device of Figure 1;
Figure 3 is a perspective view of the device of Figure 1 with a portion removed.
Fig. 4 schematically shows the optical configuration of the acquisition system of the device of Fig. 1, and the reflective element has been removed for clarity.
Figures 5A-5C schematically show, in a non-scale, the three possible positions of the device of Figure 1 during use.
Figure 6 shows a station for testing tires according to the invention.
Figure 7 schematically shows an example of an acquisition system.

6, reference numeral 100 denotes a station for inspecting a tire in a tire manufacturing line.

Preferably, the station includes a support 120 designed to support a tire 101 (e.g., a fifth wheel) that rotates the tire about a rotational axis 140 (preferably vertically aligned) and lies horizontally on one side, .

Reference numeral 106 denotes the upper bead of the tire, 105 denotes the upper sidewall, 104 denotes the upper shoulder, and 103 denotes the crow.

The station 100 includes a device 1 for inspecting a tire.

Preferably, the station includes a moving member 102 (only schematically shown) in which the device 1 is installed to move in space. Preferably, the moving member of the device is a robot arm. Preferably, the moving member is an anthropomorphic robot arm. Preferably, the moving member is an anthropomorphic robot arm moving at least five axes. In the drawing, reference numeral 10 denotes the direction of the end axis of the robot arm, for example, the cylindrical symmetry axis of the flange 3. Advantageously, during use, the device 1 is inserted into the tire from the top, not from the bottom.

The device (1) comprises a support frame (2) designed to be mounted on a moving member of the device by means of said flange (3) fixed integrally to the support frame.

The device 1 comprises an acquisition system 4 for acquiring a three-dimensional image of the surface of the tire, the acquisition system comprising a matrix camera 5 having an optical axis 6, And a linear laser source 7 designed to emit a linear laser beam having a laser beam 9 thereon.

Preferably, the acquisition system includes a first section 16 and a second section 16, respectively, for identifying the second section 31 and the first section 14 of the optical axis and the second section 32 and the first section 16 of the propagation axis, ) And the optical axis (6) and includes a reflective element (11) provided on the support frame. The first section 16 and the second section 32 of the propagation axis are straight sections that are incident on the reflective surface at each incidence point and are symmetrical with respect to a line perpendicular to the reflective surface at each incidence point.

The first section 14 and the second section 31 of the optical axis are straight sections that are incident on the reflective surface at each incidence point and are symmetrical with respect to a line perpendicular to the reflective surface at each incidence point.

Typically, each of the first sections 14,16 is located at the side of the linear laser source 7 and the matrix camera 5 for each incidence point.

Preferably, the first angle 50 formed between the first section and the second section of the optical axis 6 is an obtuse angle.

Preferably, the second angle 51 formed between the first section and the second section of the propagation axis 9 is an obtuse angle.

For example, the reflective surface and the third angle 13 formed between the optical axes in the second section 31 and / or the first section 14 is about 35 degrees.

For example, the reflective surface and the fourth angle 15 formed between the propagation axis 9 in the second section 32 and / or the first section 16 is about 35 degrees.

Preferably, the matrix camera 5, the linear laser source 7, and the reflective element are integrally fixed to the frame at each fixed position relative to the frame. That is, during use, no movement to the frame is provided.

Preferably, the support frame 2 comprises an elongated upright portion 20 which has been deployed along a first direction 21, said upright portion having a first end provided with the flange 3 and a second end along the first direction, And a second end opposite the first end.

Preferably, the frame includes an elongated crossbar 24 that is deployed along a second direction 25, the crossbar having a first end 26 integrally secured to the second end 23 of the upright portion, And the second end is a free end, and the reflective element 11 is integrally installed at the second free end 27 of the crosspiece.

For example, the first direction and the second direction are perpendicular to each other and are all perpendicular to the end shaft 10 of the robot arm during use.

In the illustrated example, the first rectilinear section 16 of the propagation axis 9 is parallel to the second direction 25. However, the present invention is also applicable to the case where the first straight section of the optical axis 6 is parallel to the second direction 25 (not shown) or the first straight section of the optical axis 6 and the first straight section of the optical axis 6 It is contemplated that all of the true line sections are not exactly parallel to the second direction 25, but form a small angle of, for example, 15 degrees or less.

For example, the propagation plane 8 is parallel to the first direction 21.

Preferably, the linear laser source 7 and the matrix camera 5 are mounted on the support frame at the second end 23 of the upright portion.

However, in an alternative embodiment (not shown) of the present invention, the laser source and / or the matrix camera 5 may be installed in the upright portion 20 at a distal position from the second end 23 of the upright portion. In this case, preferably, in the section projecting from the matrix camera, in the section projecting from the optical axis 6 and / or the linear laser source 7, the propagation axis 9 is parallel to the first direction 21 Substantially parallel, and each further reflective element is further provided, which can deflect the respective optical paths towards the reflective element 11.

In the preferred arrangement shown in the figure, the reflection element 11 is arranged below the reflective element 11 in the traveling direction of the linear laser beam or between the matrix camera 5 and the linear laser source 7 and the reflective element 11, There are no additional (reflective or refractive) elements that can tilt the optical axis of the propagation axis 9 or the optical axis 6. Consistently, the first straight section 14 of the optical axis 6 covers the entire path from the matrix camera 5 to the reflective element 11, and the first straight section 16 of the propagation axis 9, Covers the entire path from the linear laser source 7 to the reflective element 11.

Preferably, the linear laser source 7 and the matrix camera 5 lie side by side and the first section 14 of the optical axis 6 and the first section 16 of the propagation axis 9 are, for example, Is placed in a common plane, perpendicular to the plane (8).

For example, a fifth angle 30 formed between the second section 31 of the optical axis 6 and the second section 32 of the propagation axis 9 is about 15 [deg.], And is located below the reflective element 11 with respect to the propagation direction.

For example, the optical axis 6 and the second sections 31, 32 of the propagation axis 9 meet at point P,

For example, the reflective element 11 may include a base body 40 and a physically flat reflective surface 12, preferably plate-shaped, integrally affixed to the second end 27 of the crosspiece 24. [ And an optical element 41 fixed to the base body. Alternatively (not shown), the reflective surface includes two distinct sub-portions, one sub-portion for the laser beam and the other sub-portion for the optical field of the matrix camera 5 .

Preferably, the reflective surface 12 is the outer surface of the optical element 41 facing the linear laser source 7 and the matrix camera 5. Applicants have noted that the reflective surface within a mirror is typically a back surface located behind the transparent material of the mirror to protect the mirror from accidental contact. However, the Applicant has noted in the present invention that the presence of a transparent material can lead to a phenomenon, i.e. a minor "ghosting" phenomenon, which can result in an image to be obtained with a doubly reflected laser line: May occur due to the transparent material (e.g., protective glass) in addition to the actual reflective surface, which is difficult in subsequent processing.

Preferably, the optical element 41, the reflective surface 12 and the base body 40 are tapered from the distal end to the proximal end relative to the matrix camera 5 and the linear laser source 7.

4 is a top view of an exemplary optical diagram of an acquisition system of the present invention without a reflective element 11 for clarity. The introduction of the reflective element 11 according to the invention results in the deflection of the optical path in relation to that shown in figure 4, which is obvious to a person skilled in the art, but does not deviate from the principle shown in figure 4 .

Typically, the matrix camera 5 has a machine body 5a, a sensor defining an image plane 29, an objective lens 28 with said optical axis 6, a focal plane 17 and a depth of field (Fig. 4 illustratively shows end planes 18, 19 of depth of field).

4, the lining plane is perpendicular to the propagation plane 8.

Preferably, the focal plane 17 also passes through the point P.

It is assumed that the inner surface of the tire lies on the lining plane 35 which is substantially orthogonal to the propagation axis 9 during acquisition. The "lining plane" of the surface portion is an arbitrary plane passing through a plane passing a predetermined height of the surface portion of the tire, preferably the middle height of the maximum excursion of the surface height.

Preferably, the image plane 29 of the sensor of the matrix camera 5 passes through the objective lens and has a reference plane 33 (schematically shown) perpendicular to the optical axis, as schematically shown in Fig. 4, Forming an angled corner 34 on the side with the source 7, which is for example 10 [deg.].

In this way, the focal plane 17 forms a very small angle 30 with the propagation plane 8 and the depth of field in the region of interest around the lining plane 35 of the surface (where the height of the surface expands) And spreads around the propagation plane 8, which facilitates focusing of the linear laser beam which can look at the surface along the desired height excursion at the aperture stop.

It is possible to carry out a method of inspecting the tire of the present invention by using the device 1. [

The tire 101 to be inspected is arranged to horizontally lay the side of the tire on the support 120 set to rotate the tire around the full axis 140 of the tire.

The device for inspecting the tire is approached from above to insert at least the reflective element 11 into the inner space of the tire (Figs. 5A-C).

Due to the rotation, a series of segmented linear portions of the first inner surface area are successively located at least at the depth of field of the matrix camera 5 at the propagation plane 8. [

The acquisition system is continuously activated during rotation to repeat the following steps in succession:

Illuminating a linear portion of the inner surface with a linear laser beam;

Acquiring an individual matrix image of each internal surface portion including a linear portion of each internal surface; viewing the matrix image from the angle of the matrix camera, the matrix image comprises a laser line reflected by a respective linear surface portion;

Processing the matrix image to identify individual reflected laser lines;

Processing each reflected laser line by triangulation to obtain individual three-dimensional images of the linear surface portion containing information related to the elevation profile of the linear surface portion.

In this manner, a series of individual three-dimensional images of a series of individual linear portions of the first internal surface area are obtained, and a complete three-dimensional image of the first internal surface region is obtained as a result of combining the acquired series of three- Loses.

In order to improve the recognition rate of the three-dimensional image, the step of trimming the obtained matrix image along a direction substantially perpendicular to the laser line transformed into the matrix image is refined, Is 200 pixels or less.

5A, preferably the first region is the circumferential region of the inner surface of the upper shoulder 104. As shown in FIG. The "first region "," second region ", and "third region" do not necessarily mean a corresponding time sequence.

Preferably, in the same device 1, the steps are repeated to obtain a complete three-dimensional image of the (second) circumferential inner surface area of the top sidewall 105 (FIG. 5B).

Preferably, in the same device 1, it is contemplated that the above steps are repeated to obtain a complete three-dimensional image of the circumferential inner surface area of the upper bead 106 (FIG. 5C).

As described above, the present invention relates to an apparatus and method for obtaining images of both the inner surface of a bit as well as the inner surface of a sidewall and the inner surface of a shoulder, after proper movement (translational and / or tilting movement) It is possible.

Figure 7 schematically shows a straight line acquisition system 200 with a separate angle 107 formed by the first and second sections of the laser propagation axis and / or by the first and second sections of the camera optical axis.

In this case, in order to obtain a 3D image of the inner surface of the shoulder 104, the reflective element is located closer to the inner surface than in the device 1 described above, which in turn increases the risk of impulse.

In principle, it is also possible to additionally tilt the reflecting surface of the acquisition system 200 with respect to the center plane of the camera, such that the optical axis of the camera and / or the propagation axis of the laser is kept radially backward. For example, referring to FIG. 7, the acquisition system 200 is additionally rotated counterclockwise. This additional rotation, however, causes additional operational limitations of the acquisition system 200, for example, to avoid collision with the upper bead 106.

Finally, the acquisition system 200 requires that the distance between the reflective element and the camera and / or the laser be a greater distance relative to the acquisition system 1 described above, depending on the specific connection and / or form with the mobile system can do.

If the acquisition system 200 is used to acquire images of the upper bead 106, then the acquisition system 200 may also be configured to provide a larger constraint (s) to the device 1 to avoid the acquisition system itself becoming impulsive with the upper bead portion and / ≪ / RTI >

Claims (36)

A device (1) for inspecting a tire,
The apparatus comprises:
A support frame 2;
A flange (3) fixed to the support frame (2) for attaching the support frame to the movable member (102) of the device; And
And an acquisition system (4) for acquiring a three-dimensional image of the surface of the tire,
The acquisition system is installed in a support frame,
The acquisition system comprising:
A matrix camera (5) having an optical axis (6);
- a linear laser source (7) designed to emit a linear laser beam having a propagation plane (8) and a propagation axis (9); And
A radio wave propagating through the propagation axis 9 to identify the first section 16 and the second section 32 of the propagation axis 9 and the first section 14 and the second section 31 of the optical axis 6, And a reflective element (11) having a reflective surface (12) intersecting both the optical axis (6)
The first section 16 and the second section 32 of the propagation axis 9 are linear sections incident on the reflective surface 12 at the individual incidence points and the first section 16 and the second section 16 of the propagation axis 9, The second section 32 is mirror-symmetric with respect to a line perpendicular to the reflective surface 12 at the individual incidence points,
The first section 14 and the second section 31 of the optical axis 6 are linear sections incident on the reflective surface 12 at the individual incidence points and the first section 14 and the second section 31 of the optical axis 6, The second section 31 is mirror-symmetric with respect to a line perpendicular to the reflective surface 12 at the individual incidence points,
The first sections 14 and 16 are respectively located on the sides of the matrix camera 5 and the linear laser source 7 for each incident point,
The first angle 50 formed between the first section 14 and the second section 31 of the optical axis 6 is an obtuse angle,
A second angle (51) formed between the first section (16) and the second section (32) of the propagation axis (9) is an obtuse angle. The method according to claim 1,
A device for inspecting a tire in which the optical axis (6) in the first section (14) or the second section (31) and the third angle (13) formed between the reflective surface (12) are 20 degrees or more and 40 degrees or less. 3. The method according to claim 1 or 2,
Wherein the fourth angle (15) formed between the propagation axis (9) and the reflective surface (12) in the first section (16) or second section (32) is greater than or equal to 20 degrees and less than or equal to 40 degrees. 4. The method according to claim 2 or 3,
Wherein the third angle (13) is greater than 30 degrees and the fourth angle (15) is greater than 30 degrees. 5. The method according to any one of claims 1 to 4,
The matrix camera (5), the linear laser source (7), and the reflective element (11) are fixed integrally to the support frame (2) in separate, fixed positions relative to the support frame (2). 6. The method according to any one of claims 1 to 5,
The support frame 2 comprises an upright portion 20 of elongated form with a main deployment along a first direction 21,
Said upstanding portion having a first end (22) at which the flange (3) is installed and a second end (23) at the opposite end of the first end (22) along the first direction. The method according to claim 6,
The support frame 2 includes an elongated crossbar 24 having a major deployment along the second direction 25,
The crossbar has a first end 26 at a second end of the upright portion 20 and a second end 27 opposite the first end 26 along a second direction 25, The end portion 27 is a free end,
The reflective element (11) is installed at the second end (27) of the crosspiece (24). 8. The method of claim 7,
Wherein the first direction (21) and the second direction (25) are substantially perpendicular to each other. 9. The method according to claim 7 or 8,
The first section 14 of the optical axis 6 is substantially parallel to the second direction 25 or the first section 16 of the optical axis 9 is substantially parallel to the second direction device. 9. The method according to claim 7 or 8,
The first section 14 of the optical axis 6 is substantially parallel to the second direction 25 and the first section 16 of the propagation axis 9 inspects a tire substantially parallel to the second direction device. 11. The method according to any one of claims 6 to 10,
Wherein the propagation plane (8) at least in the first section (16) of the propagation axis (9) is substantially parallel to the first direction (21). 12. The method according to any one of claims 1 to 11,
The first section (14) of the optical axis (6) extends from the matrix camera (5) to the reflective surface (12). 13. The method according to any one of claims 1 to 12,
The first section (16) of the propagation axis (9) extends from the linear laser source (7) to the reflective surface (12). 14. The method according to any one of claims 6 to 13,
Wherein said linear laser source and said matrix camera are mounted on a support frame at a second end of said upright portion. 15. The method according to any one of claims 1 to 14,
Wherein said linear laser source (7) and said matrix camera (5) are arranged side by side. 16. The method according to any one of claims 1 to 15,
A first section (14) of the optical axis (6) and a first section (16) of the propagation axis (9) are placed on a common plane substantially perpendicular to the propagation plane (8). 17. The method according to any one of claims 1 to 16,
A fifth angle (30) formed between the second section (31) of the optical axis (6) and the second section (32) of the wave axis (9) is greater than or equal to 5 degrees and less than or equal to 40 degrees. 18. The method of claim 17,
The fifth angle (30) is a device for inspecting a tire of 20 DEG or less. 19. The method according to any one of claims 1 to 18,
An apparatus for inspecting a tire which does not have further reflective elements along the propagation axis (9) or the optical axis (6) beyond the reflective element (11), downstream of the reflective element (11) with respect to the propagation direction of the laser beam. 19. The method according to any one of claims 1 to 18,
An apparatus for inspecting a tire which is beyond the reflective element (11), downstream of the reflective element (11) with respect to the propagation direction of the laser beam, and which has no additional reflective elements along the propagation axis (9) and the optical axis (6). 21. The method according to any one of claims 1 to 20,
The reflective element 11 comprises a base body 40 and an optical element 41 having a reflective surface 12 and secured to the base body 40. 22. The method according to claim 7 or 21,
The base body 40 is integrally fixed to the second end 27 of the crosspiece 24,
The reflective surface (12) is a single physical surface and is intended to inspect a flat tire. 22. The method of claim 21,
Wherein the reflective surface (12) is an outer surface of an optical element (41) facing the linear laser source (7) and the matrix camera (5). 22. The method of claim 21,
The optical element (41) inspects a tire tapered from the proximal end to the winner end with respect to the matrix camera (5) or the linear laser source (7). 25. The method according to any one of claims 1 to 24,
Said reflective surface (12) inspecting a tapered tire from a proximal end to a winner end with respect to a matrix camera (5) or a linear laser source (7). 22. The method of claim 21,
Wherein the base body (40) inspects a tapered tire from the proximal end to the winner end with respect to the matrix camera (5) or the linear laser source (7). 27. The method according to any one of claims 1 to 26,
The matrix camera 5 has a sensor defining an image plane 29, an objective lens 28 with an optical axis 6, a focal plane 17, and a depth of field,
The image plane 29 forms an acute angle 34 with a reference plane 33 passing through the objective lens and perpendicular to the optical axis and a vertex on one side on which the linear laser source 7 is arranged, The plane 17 forms an angle of 45 DEG or less with the propagation plane 8,
Wherein the acute angle (34) between the image plane (29) and the reference plane (33) is greater than or equal to 5 degrees and less than or equal to 20 degrees. 28. The method according to any one of claims 1 to 27,
The matrix camera 5 is designed to obtain a matrix image of a part of the surface, and in the individual machine body 5a, comprises a processing unit,
The processing unit comprising:
Identifying a reflected laser line representing a laser line generated by illumination of a laser beam and a linear portion of the surface portion in a matrix image;
Processing the reflected laser line through a triangulation to obtain a three-dimensional image comprising information about the elevation profile of the linear portion of the surface portion;
To select the sub-portion of the acquired matrix image along a direction substantially perpendicular to the reflected laser line in the matrix image itself; Respectively,
The tasks of identifying the laser line and processing the reflected laser line through triangulation are performed on the sub-part of the image, and after the operation of selecting the sub-part of the acquired image, A device for testing a tire having a number of pixels less than or equal to 200 pixels along one direction. A station (100) for inspecting a tire in a tire production line,
The station comprises a support (120) designed to rotate the tire about the axis of rotation (140) of the tire and to support the tire (101) mounted on the side wall and a tire according to any one of claims 1 to 28 (1), the device
The apparatus (1) is a station for inspecting a tire installed on a moving member (102). Arranging a tire (101) to be inspected;
28. A method for testing a tire according to any one of claims 1 to 28, comprising the steps of:
Inserting at least the reflective element (11) in the tire interior space;
Illuminating a linear portion of the inner surface of the tire with a linear laser beam to create a laser line;
The matrix image comprising a reflected laser line representing the laser line, the method comprising the steps of: obtaining a matrix image of an inner surface portion comprising a linear portion of an inner surface;
In the matrix image, identifying the reflected laser line; And
And processing the reflected laser line through triangulation to obtain a three-dimensional image of the linear surface portion including information about the elevation profile of the linear surface portion. 31. The method of claim 30,
Selecting a sub-portion of the acquired matrix image along a direction substantially perpendicular to the reflected laser line in the matrix image itself,
Identifying the reflected laser line and processing the reflected laser line through triangulation are performed on a sub-portion of the image. 32. The method according to claim 30 or 31,
Translating the first inner surface area of the tire relative to the instrument such that a series of segmented linear portions of the first inner surface area are continuously located within the depth of field of the matrix camera (5) at least in the propagation plane In addition,
In order to obtain a series of three-dimensional images of a series of delimited linear portions of the first internal surface area, the acquisition system 4 includes steps of illuminating with a linear laser beam, acquiring an individual matrix image, Wherein said step of identifying said plurality of laser beams comprises the steps of: identifying a plurality of laser beams, identifying said plurality of laser beams, processing said individually reflected laser lines,
A series of three-dimensional images obtained on a series of linear inner surface portions are combined to obtain a complete three-dimensional image of the first inner surface portion,
Wherein the first inner surface area is an inner surface area of the shoulder (104) of the tire. 33. The method according to any one of claims 30 to 32,
Translating the second inner surface area of the tire relative to the instrument such that a series of segmented linear portions of the second inner surface area are continuously located within the depth of field of the matrix camera (5) at least in the propagation plane,
In order to obtain a series of three-dimensional images of a series of delimited linear portions of the second internal surface area, the acquisition system 4 includes steps of illuminating with a linear laser beam, acquiring an individual matrix image, Wherein said step of identifying said plurality of laser beams comprises the steps of: identifying a plurality of laser beams, identifying said plurality of laser beams, processing said individually reflected laser lines,
A series of three-dimensional images obtained on a series of linear inner surface portions are combined to obtain a complete three-dimensional image of the second inner surface portion,
Wherein the second inner surface area is an inner surface area of the side wall (105) of the tire. 34. The method according to any one of claims 30 to 33,
Translating a third inner surface area of the tire relative to the instrument such that a series of segmented linear portions of the third inner surface area are continuously located within the depth of field of the matrix camera (5) at least in the propagation plane,
In order to obtain a series of three-dimensional images of a series of delimited linear portions of the third internal surface area, the acquisition system 4 includes steps of illuminating with a linear laser beam, acquiring an individual matrix image, Wherein said step of identifying said plurality of laser beams comprises the steps of: identifying a plurality of laser beams, identifying said plurality of laser beams, processing said individually reflected laser lines,
A series of three-dimensional images obtained on a series of linear inner surface portions are combined to obtain a complete three-dimensional image of the second inner surface portion,
Wherein the third inner surface area is an inner surface area of the bead (106) of the tire. 35. The method according to any one of claims 30 to 34,
The tire to be inspected is arranged horizontally on the side wall,
The operation of inserting at least the reflective element (11) on the inner surface of the tire is a method of inspecting a tire originating from the top. 36. The method of claim 35,
Wherein at least one of the first inner surface area, the second inner surface area, and the third inner surface area belongs to the upper half-part of the tire with respect to the center line plane.

Images